The age of demons has begun. Dr. Faust, having foreseen the rise of evil, is near death and cannot confront the impending threat himself. He entrusts a young boy, Shingo Yamada, with the responsibility of ridding the Earth of this new evil. Faust discovers a birthmark on Shingo’s forehead that marks him as the chosen demon fighter. From hell, Faust summons Mephisto, a devil who is less than enthusiastic, who may be humanity’s only hope of survival. After sealing a blood pact to save humankind, Shingo and Mephisto set out to battle the supernatural world.